This traditional Italian pastry is similar to a doughnut and is filled with a rich vanilla cream.
7g sachet dried yeast (see note)
75g caster sugar, plus extra for rolling
3 1/3 cups (500g) plain flour
300ml warm milk
Grated rind of 1 lemon
75g softened unsalted butter, chopped
1L vegetable oil, for frying
6 egg yolks
100g caster sugar
40g plain flour
2 teaspoons vanilla extract
Step 1) For pastry cream, beat yolks and sugar until pale. Sift in flour, whisking to combine. Place milk in a pan and bring to scalding point, then add to egg mixture.
Step 2) Turn heat to low and return mixture to pan, stirring constantly until thick. Add vanilla, then transfer to a bowl and cover with plastic wrap. Refrigerate to chill.
Step 3) For bomboloni, place yeast in a small bowl with 1 tablespoon each of sugar and flour. Stir in warm milk. Set aside in a warm place for 15 minutes until mixture bubbles and froths.
Step 4) Place remaining sugar and flour in a bowl with rind and butter, then add yeast mixture. Using your hands, combine mixture, then turn onto a floured board.
Step 5) Knead for 5 minutes until smooth and elastic, then place in a lightly oiled bowl, cover with a clean tea towel and set aside in a warm place to rise for about 2 hours.
Step 6) When dough has nearly doubled in size, punch it down with your fist. Use a rolling pin to roll out dough on a lightly floured surface to about 1cm thick. Use a 4cm pastry cutter to make 24 rounds and place on a baking tray (allowing a little room to expand). Cover with a tea towel and set aside to rise for another hour.
Step 7) Heat oil in a deep-fryer or heavy-based saucepan and heat to 180°C. (If you don't have a deep-fryer thermometer, test a cube of bread - it should turn golden in about 2 minutes.) You don't want oil too hot, as the bomboloni will darken before the inside is cooked, so adjust heat if necessary. Fry, 3 or 4 at a time, until golden. You may need to turn with tongs. Remove with tongs or a slotted spoon and drain on paper towels. While still warm, roll in extra sugar. Cool completely.
Step 8) Just before serving, use a sharp knife to make a slit in the bomboloni and pipe or spoon in the pastry cream filling.